Gun type casing perforator



Marci! 10, 1942. C, Q COLE 2,276,161

GUN TYPE CASING PERFORATOR Filed July 5, 1940 INVENTOR.

Patented Mar. 10, 1942 UNITE STATES PATENT OFFICE" GUN TYPE CASING PERFORATOR bawthern 0. Cole, Whittier, Calif. Application July 5, 1940, Serial No. 344,115

21 Claims.

This invention relates to improvements in gun perforators of the type intended for perforating casing in well bores.

Included in the objects of my invention are the following:

First,to provide a novelly constructed projectile,

the use of which compensates for the restricted barrel length of perforating guns adapted for operation inside of well casing.

Second, to provide an explosive receptacle of novel construction which may be readily assembled on the projectile.

Third, to provide a novel gun constructed to receive the projectile and explosive receptacle and incorporating a seal resistant to external fluid pressure and particularly rugged electrical conductors and contacts.

Other objects and advantages of the invention will become apparent hereinafter and in the accompanying illustrative drawing, in which:

Fig. 1 is a transverse sectional view through a cylindric gun body showing the projectile barrel, explosion chamber and breech bore, in longitudinal section, the projectile in elevation and the explosive receptacle partly in elevation and partly in longitudinal section.

Fig. -2 is a view of the projectile partly in elevation and partly in longitudinal section.

Fig. 3 shows an explosive receptacle end in longitudinal section.

Fig. 4 is a view of the explosive receptacle, less the end illustrated in Fig. 3, in longitudinal section and the electrical contact and firing members in elevation.

Referring to Fig. 1, 5 designates the gun body which provides the laterally directed and threaded bore 6, explosion chamber 1 and breech bore 8. Barrel 9, providing wrench sockets Ill My projectile as illustrated in Fig. 2 comprises penetrating end l9, rearward end'\2i!. bore 38 formed therein, opposing faces 2| and 22 and the intervening connecting portion 23.

26 and 21, eachproviding outer and inner skirts 36, 31 and 35, 34 respectively.

Split, electrical contact plug 28 is insulated from skirted end 21 by means of bushing 29 and has secured to its inner end detonating wire 30 which in turn is grounded to shell at 3|.

In the assembly of the cartridge upon the projectile, the end 20 thereof is passed through the loop of detonator and into skirted aperture 32, making a tight fit therewith.

The shell is then filled with an explosive material 33 and end 26 forced into position, the outer skirt 36 engaging the inner surface of shell 25 and inner skirt 31, engaging projectile end IS. The fit in each case being sufiiciently tight to permit handling. The assemblage as above described is clearly illustrated in Fig. l, in which it will be noted that projectile end 20 is inserted in breech bore 8 and plug 28 is received by and makes electrical contact with socket l6. Conductor rod l5 extends to a controlled source of electrical energy for actuating detonator 30.

The patent literature affords examples of cylindric type perforating guns providing laterally directed bores and incorporating electrical firing circuits, consequently such circuits are not illustrated here.

With projectile and explosive cartridge positioned in the gun, as above described, and with barrel 6 and sealing member M in place, all as illustratedin Fig. v1, detonation of the explosive causes explosion pressure to be exerted against the projectile opposing faces 2| and 22, thereby subjecting the connecting portion 23 to longitudinal tension. For'a given pressure in the explosion chamber the force actingagainst faces 2| and In Figs. 3 and 4, which illustrate the explosive receptacle or cartridge of my invention, '25

designates the outer shell thereof; said shell being 22 depends upon the areas thereof. In the practice of my invention I prefer to construct the projectile with faces of such an area and bore 2| of such a size that rupture of portion 23 occurs when substantially maximum explosive pressure is reachedin the explosion chamber; bore 38 being for the purpose of decreasing the resistance of portion 23 to tension or break. For given areas of faces 2| and 22 the magnitude of the pressure in the explosion chamber required to rupture portion 23 is determined by the size of recess or bore 38.

Thus it will be seen that I have provided a projectile for use in the short barrel of a gun perforator the propulsion of which is delayed until maximum explosive pressure is reached and conand barrels for gun type perforators," flied August '1, 1939, Serial No. 288,853, I describe a projectile for gun perforators which, however, bears no structural relationship tothe invention herein disclosed.

It will be seen that my invention is subject to various modifications. By way of examples, rearward face 22 maybe made larger, but obviously not smaller than face 22. Bore 38 may be extended and enlarged at its inner end so that break will occur adjacent face 2|. Although I prefer to insert projectile end 20 in breech bore 8, it will be apparent that a skirted end 21 or like element may serve as a seal to prevent pressure building up behind the projectile. It will further be seen that faces 2| and 22 may take any formso long as the effect of explosive pressure thereagainst is to rupture portion 23.

Although I have described and illustrated in being at least as great as that of the forwardface, and means connecting said faces rupturable by total explosive propulsive pressure exerted against said faces.

3. A projectile for gun perforators comprising a penetrating end, a rearward end and an intervening connecting portion of reduced cross-sectional area relative to said ends whereby oppos-' ing faces are formed, said portion being rupturable by total high explosive propulsive pressure against said faces and resistant to rupture at initial pressure.

4., A projectile for gun perforators comprising a penetrating end, a rearward end and an intervening connecting member of reduced diameter relative to said ends whereby opposing faces are provided, said member being rupturable by total propulsive pressure against said faces.

5. A projectile for gun perforators providing siirfaces arranged in opposition and intervening connecting portions rupturable by total explosive propulsive pressure against said surfaces.

6. A projectile for gun perforators comprising a forward end, a rearward end providing a bore, and a portion of less outside diameter than 'said ends connecting the same together whereby opposing surfaces are formed, said portion being frangible by total explosive, propulsive pressure against said surfaces.

'7. A cartridge for-gun perforators comprising an outer shell, annular ends in said shell having outer and inner peripheral skirts directed into said shell.

8. A cartridge for gun perforators comprising an outer shell, annular ends in said shell having outer and innerperipheral skirts directed into said shell, and including electrical contact and detonating means.

9. In a gun perforator a gun body providing a muzzle bore, rearwardly therefrom a breech bore and an explosion chamber having a relatively greater area than said bores intermediate the same.

10. In:a gun perforator a gun body providing an explosion chamber, a breech bore in the reare ward wall thereof, a counterbore at the outward end, a bored barrel in said counterbore and means securing said barrel in said counterbore. I

11. A combination as in claim 10; said barrel providing a counterbore at the muzzle thereof and sealing means therein.

12. In a gun perforator the combination of a cartridge having apertured ends, the outer and aperture peripheries thereof having inwardly directed skirts, a projectile extending through said apertures and engaging the skirts thereof, said projectile having a portion of reduced section inside ofsaid cartridge whereby opposing faces are formed.

13. In a gun perforator the combination of a projectile and an explosive receiving cartridge,

said projectile extending through said cartridge and outwardly therefrom and having a portion of reduced cross-sectional area inside of said cartridge whereby opposing surfaces are formed, said portion being rupturable by total explosive propulsive force against said surfaces.

14. In a gun perforator, a gun body providing a muzzle bore, rearwardly therefrom a breech bore and an explosion chamber intermediate said bores, a projectile comprising a penetrating end, a rearward end and an intervening connecting portion of reduced cross-sectional area whereby opposing surfaces are formed, said penetrating end positioned in said muzzle bore, said rearward end positioned in said breech bore and said intervening connecting portion extending across said explosion chamber, the opposing surfaces facing into said explosion chamber.

15. A combination, as in claim 14, including an explosive receiving cartridge mounted on said projectile and positioned in said explosion chamber.

16. In a gun perforator the combination of, a gun body providing an explosion chamber, a breech bore in the rearward wall thereof, a counterbore at the outward end, a bored barrel in said counterbore and means releasably securing the same therein; a projectile having its penetrating end positioned in said barrel bore,

. its rearward end in said breech bore and a connecting portion of reduced cross-sectional area between said projectile ends extending across said explosion chamber, said projectile ends thereby providing opposing surfaces facing into said explosion chamber; an explosive receiving cartridge mounted on said projectile and positioned in said explosion chamber; electrical con- ,tact and detonating means for firing a charge of explosive in said cartridge and including sealing means in the muzzle end of said barrel bore.

17. In a gun perforator, the combination of, a body having a barrel formed therein, an explosion chamber rearwardly therefrom, a projectile having its penetrating end positioned in said barreland its rearward end in said chamber and having a portion of relatively restricted section securing said ends together whereby oppos-' ing surfaces are formed facing into said chamber, said portion being rupturable by explosive pressure against said surfaces and sealing means adjacent said rearward end whereby total, explosive, propulsive pressure is prevented from building up rearwardly of said end. a

18. A projectile for gun perforators providing opposing surfaces, a recess extending from the rearward end thereof and a member connecting said surfaces rupturable adjacent the longitumeans connecting said surfaces resistant to rupture by initial explosive pressure exerted against said surfaces and rupturable by subsequent total,

propulsive pressure against the same whereby the propulsion of said projectile is delayed until maximum explosion force is built up.

21. In a gun perforator the combination of a projectile and an explosive receiving cartridge mounted thereon, said projectile extending through said cartridge and providing opposing surfaces facing into the same and means connecting said surfaces rupturable by total explosive propulsive pressure thereagainst.

C. C. COLE. 

